If you're just curious about lighting comments, then I'd say the lighting in the second one is pretty neat. Somehow the first one came off really harsh and didn't do good things for his skin and such. (though airbrushing could help that if you loved the shot for whatever reason)

As a non-lighting comment, I really dislike 2 things with kid pictures...

1. Characters on anything... it just takes away from the shot IMO.
2. Diapers. Diapers are gross, esp. when they are bulging from being ready to be changed. I think us parents just kinda get used to them and don't even think about it, but when you stop and think for a sec... it's like... ew?

BTW... cute boy you have there. (and no, I don't say that about all babies... I think most babies are kind ugly.) :^)